Universally adjustable pressure pad



Dec. 13, 1966 Filed April 15, 1964 F. D. PIERCE 3,291,008

UNIVERSALLY ADJUSTABLE PRESSURE PAD 2 Sheets-Sheet 1 FIG. .1.

FIG. 2

INVENTOR FRANK D. PIERCE BY ""f' ATTORNEY Dec. 13, 1966 F. D. PIERCE 3,291,008

UNIVERSALLY ADJUSTABLE PRESSURE PAD Filed April 13, 1964 2 Sheets-Sheet 2 INVENTOR. FRANK D. PIERCE B ALMA,

ATTORNEY United States Patent 3,291,008 UNIVERSALLY ADJUSTABLE PRESSURE PAD Frank ll). Pierce, Salinas, Calif, assignor to Klemark, Inc., Salinas, Calif, a corporation of California Filed Apr. 13, 1964, Ser. No. 359,268 3 Claims. ((11. 9336.3)

In portable and relatively light weight box making equipment for bottom sealing of corrugated cartons, boxes and the like, at their point of use, practically all types of machines use a vertical ram and a solid pressure pad which travels vertically downward through the set-up box and presses against the inside bottom of the box to form a solid working surface against which the anvil and its activating leverage can work with upward pressure to hold the glued box tabs in place, at least momentarily, until the glue has set and the bottom of the box is sealed.

There is so much variation in the thicknesses of corrugated boards and other types of fabricated materials from which boxes are made, even in the same runs, that the same pressure pad does not and cannot apply equal pressure against the glued bottom flaps or equal pressure over the entire area. Accordingly, the solid pad does not make a good working surface against which pressure can be exerted and because of this, frequently seals are improperly made or even missed.

Furthermore, using a single pressure plate rigidly attached to a ram, it is apparent that different sized plates are required for dilferent sized boxes. To change plates requires a take-down period and replacement time for the machine which will stop the box line long enough to make itself felt in the requirements for boxes. This may cause a stoppage of the production line and all operations ahead of the box making. Accordingly, a crossheadram assembly is here disclosed which can be adjusted in position and as to length for a limited number of boxes, and which requires a minimum take-down and replacement time interval to change pressure pad assemblies if that is required.

Further objects are to provide a construction of maximum simplicity, economy and ease of assembly and disassembly, also such further objects, advantages and capabilities as will fully appear and as are inherently possessed by the device and invention described herein.

The invention further resides in the combination, construction and arrangement of parts illustrated in the accompanying drawing, and while there is shown therein a preferred embodiment thereof, it is to be understood that the same is illustrative of the invention and that the invention is capable of modification and change and comprehends other details of construction without departing from the spirit thereof or the scope of the appended claims.

In the drawings:

FIGURE 1 is a side elevational view of the pressure pad of the invention;

FIGURE 2 is an end elevational'view as seen from the line IIII of FIGURE 1; and

FIGURE 3 is a top plan view taken on the line III-III of FIGURE 1.

With reference to the drawings, the main vertical ram is indicated at 10. The ram is secured in the ram block 11 which is drilled and tapped centrally to receive the ram 10. The ram is further held in position in the ram block by a set screw 12. There are two lateral holes 14 and 15 through the block 11. These are for securing the lateral anvil activating ties 19 to the ram block 11. Mounted on and secured beneath the ram attaching block 11 is a longitudinal tubular member 16 which is a bar mount, having a passage axially therethrough. The bar "ice mount 16 is substantially coextensive with and secured to the block 11 in any suitable manner, such as welding. Centrally and transversely through the tubular bar mount 16 is a hole 17.

Passing through theaxial passage of the bar mount 16 is a crosshead bar 18 which is retained within the bar mount by sliding frictional engagement and by means of a cotter pin 20 which passes through the transverse hole 17 registering with hole 21 in the crosshead bar at approximately its midpoint. The crosshead bar 18 will vary in length according to the size of the box on which it is intended to operate, but its over-all length for any particular operation must be less than the inner length of the set-up box. The bar 18 is therefore held in position beneath the ram 10 and extends longitudinally substantially equidistant beyond the limits of the bar mount 16.

At each end of the bar 18 is a collar 22 which fits in sliding engagement thereover. Welded or otherwise secured to the collar 22 is a pin 23 which is positioned transversely to the axis of the bar 18 and in a plane above the bar and tangentially with respect to the collar 22. The pin 23 is drilled vertically with a pair of holes 24 and 25 adjacent each end. The collar 22 is held in its outer position by a washer 26 and cotter pin 27. The holes 28 for the cotter pin 27 may be spaced along the outer end of the bar to make adjustments for length as may be required. The collar 22 is held against the Washer 26 by compression spring 30, one end of which bears against the outer end of the bar mount 16 and the other end of which bears against the inner end of the collar 22.

It is apparent that if adjustments are not required, then the collar may be positioned in any suitable manner without the requirements of the spring 30, so long as the relative movement of the collar is maintained. Also, adjustments can be provided for at one or both ends of the crosshead bar.

At each end of the pin 23 is mounted a plate member 31 having a hole 32 for sliding engagement over the pin 23. The plate member has attached to its bottom end surface a pin 33 which projects a short distance beyond the vertical limits of the plate 31. The plates 31 are retained on the pin 23 for free rotating movement between cotter pins 34 passing through holes 24 and 25 at each end of the pin 23.

The pressure pad assembly further comprises a flat plate 35 which has a pair of vertically extending triangular shaped plates 36, each having a hole 37 adjacent the apex. The plates 36 are spaced from each other a dis tance slightly greater than the width of the plate 31, and the holes 37 permit the passage therethrough of the pin 33 for free rotation thereon.

It is apparent from the assembly of each of these rnembers that the crosshead assembly shown provides four pressure pads, each of which rotate as pairs longitudinally with separate rotation laterally. In any position the weight of the pressure pad plates 35 and the free rotation of the mounting will permit them to always assume a true horizontal position. This provides a universal adjustment movement which will accommodate to varying thicknesses so that in any one lowering of the ram to the pressure position, the pressure pads will adjust to the varying thicknesses individually and accommodate to the variations so that the pressure will be equal in all instances and in a true horizontal plane.

. Iclaim:

1. In an equalizing pressure pad in combination, a longitudinal crosshead bar, a block for securing said crosshead bar and a ram, transverse bars rotatably mounted adjacent each end of said crosshead bar, lateral members rotatably mounted at each end of said transverse bars,

pressure pads mounted for swinging movement on said lateral members, and a ram for pressing said pads simultaneously against an object.

2. In an equalizing pressure pad in combination, a longitudinal crosshead bar, a block for securing said cross head bar and a ram, transverse bars mounted for transverse rotation in a vertical plane at each end of said crosshead bar, lateral members mounted for longitudinal rotation in a vertical plane at each end of said transverse bars, pressure pads having a substantial fiat contact area mounted for transverse swing movement on said lateral members, and a ram for directing said pads as a unit against a surface.

3. In an equalizing pressure pad in combination, a longitudinal crosshead bar, a block for removably securing said crosshead bar and a ram, transverse bars mounted for transverse rotation in a vertical plane at each end of said crosshead bar, said transverse bars being adjustably positionable longitudinally along said crosshead bar, lateral members mounted for longitudinal rotation in a vertical plane at each end of said transverse bars, pressure pads having a substantial flat contact area mounted for transverse swing movement on said lateral members, and a ram for directing said pads against a surface.

References Cited by the Examiner UNITED STATES PATENTS 2,381,364 8/1945 Osgood 93--36.3 2,499,960 3/ 1950 Leask 9336.3 3,154,009 10/1964 DeWyer 100295 X BERNARD STICKNEY, Primary Examiner. 

1. IN AN EQUALIZING PRESSURE PAD IN COMBINATION, A LONGITUDINAL CROSSHEAD BAR, A BLOCK FOR SECURING SAID CROSSHEAD BAR AND A RAM, TRANSVERSED BARS ROTATABLY MOUNTED ADJACENT EACH END OF SAID CROSSHEAD BAR, LATERAL MEMBERS ROTATABLY MOUNTED AT EACH END OF SAID TRANSVERSE BARS, PRESSURE PADS MOUNTED FOR SWINGING MOVEMENT ON SAID LATERAL MEMBERS, AND A RAM FOR PRESSING SAID PADS SIMULTANEOUSLY AGAINST AN OBJECT. 